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Introduction into Ratio & Proportions. Monday, December 10, 2012. At the end of this lesson you should be able to…………. Write ratios and reduce to simplest form Calculate unit rates, graph and interpret the results. Calculate and compare unit rates. 5-1. Ratios and Rates. Course 2.
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Introduction into Ratio & Proportions Monday, December 10, 2012
At the end of this lesson you should be able to………….. • Write ratios and reduce to simplest form • Calculate unit rates, graph and interpret the results. • Calculate and compare unit rates
5-1 Ratios and Rates Course 2 In basketball practice. Kathlene made 17 baskets in 25 attempts. She compared the number of baskets she made to the total number of attempts she made by using the ratio . A ratiois a comparison of two quantities by division. 17 25 Kathlene can write her ratio of baskets made to attempts in three different ways. 17 25 17 to 25 17:25
5-1 Ratios and Rates Course 2 Additional Example 1: Writing Ratios The recommended fuel for Suzanne’s snowblower is made from 80 quarts of gasoline and 1 quart of motor oil. Write each ratio in all three forms. A. quarts of gasoline to quarts of motor oil For every 80 quarts of gasoline there is 1 quart of oil. 80 1 , 80 to 1, 80:1 B. quarts of oil to quarts of fuel mixture Find the total number of quarts in the mixture. 80 + 1 = 81 1 81 , 1 to 81, 1:81 For each quart of oil there are 81 quarts of mixture.
5-1 Ratios and Rates 1 2 3 2 5 4 , 3 to 2, 3:2 , 1 to 2, 1:2 , 5 to 4, 5:4 8 16 12 8 , 8 to 16, 8:16 or , 12 to 8, 12:8 or 20 16 , 20 to 16, 20:16 or Course 2 Insert Lesson Title Here Lesson Quiz: Part 1: Writing Ratios A coin bank contains 16 quarters, 12 dimes, and 8 nickels. Write the given ratio in all three forms. 1. nickels to quarters 2. dimes to nickels 3. nickels and dimes to quarters
5-1 Ratios and Rates Course 2 A ratio that compares two quantities measured in different units is a rate. Suppose Ms. Latocki drove 75 miles in 3 hours. Her rate of travel was 75 miles in 3 hours, or . 75 mi 3 hr
5-1 Ratios and Rates Course 2 If the measure of the second quantity in a rate is one unit, then the rate is a unit rate. To change a rate to a unit rate, divide both the numerator and denominator by the number in the denominator. 75 mi 3 hr 25 mi 1 hr 75 mi ÷ 3 3hr ÷ 3 = = The unit rate 25 miles per hour expresses the average number of miles Ms. Latocki drove each hour.
5-1 Ratios and Rates Reading Math The unit rate is read as “twenty five miles per hour.” 25miles 1 hour Course 2
5-1 Ratios and Rates Course 2 Try This: Example 2A Find the unit rates and write them in both fraction and word forms. A. Harold could jog 1,000 meters in 5 minutes. 1,000 m 5 min Rate in fraction form 1,000 ÷ 5 5 ÷ 5 200 m 1 min Unit rate in fraction form = Unit rate in word form Harold jogged 200 meters per minute.
Unit Rate Comparison Kim and Ted work out on treadmills together at the gym. Kim walked 3.0 miles in 21 minutes, while Ted walked 4.5 miles in 42 minutes. Who walked at the faster rate?
Homework • Finish graphing and writing your observation. • Textbook p. 290 #1-16 and #23-29